Pseudo Random Sequence Generator

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To set the initial state of a Pseudo Random Sequence Generator using a 74LS74 D-flipflop, the preset and clear inputs can be utilized effectively. The preset and clear controls are active LOW, meaning that momentarily setting either input LOW will adjust the output Q to the desired state. Users have successfully implemented this by directly applying the 0001 sequence through the preset inputs. It is important to note that these inputs can be used asynchronously without a clock signal. Proper understanding of the function table in the datasheet is crucial for effective implementation.
challarao
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1.How to set the initial state of the Pseudo Random Sequence Generator?



2. I'm using 74LS74 D-flipflop.I'm unclear how to use clear and preset enable inputs to set the initial sequence.



3. I tried doing the experiment by directly giving the 0001 sequence through respective D-flipflop's preset inputs.But, I came to know that preset enable inputs, without clock input can be used to give asynchronous input.But, I didn't get any clear idea about how to set any initial sequence for this.Please help me...Please give some reference links...I googled but no direct material is available...My problem lies in not knowing using the preset-enable and clear inputs of 74LS74...please tell how to do that...
 
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According to the datasheet http://www.datasheetsite.com/extpdf.php?q=http%3A%2F%2Fwww.tranzistoare.ro%2Fdatasheets2%2F68%2F68908_1.pdf the PRESET and CLEAR controls are active LOW. Momentarily set one or the other LOW to set Q to what you need. See the FUNCTION TABLE.
 
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Thanks for reply...
I have seen that and it's working now...
 
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